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Noise Pollution: Headphones Could Be Damaging Your Health

It should not be surprising that noise, when excessive, can have a damaging effect on our health. Moreover, you may be exposed to this form of "pollution" even without realizing it.

The term noise pollution is typically associated with loud motor vehicles, construction work, airports, or children screaming. But the category also includes "leisure noise" which is sourced from leisurely or fun activities, as opposed to being a nuisance.

Some common sources of leisure noise include nightclubs, concerts, fitness classes, live sporting events, or simply listening to loud music played from headphones or earphones.

According to the World Health Organization, more than a billion teenagers and young adults are at risk of hearing loss due to such personal listening devices. The safest way to use headphones is at around 60 percent volume, the agency has noted, ideally no longer than an hour per day.

But the heightened risk of tinnitus aside, excessive noise levels can damage a lot more than our hearing ability. One review from 2015 noted noise exposure could increase the production of stress hormones in the body, which is linked to high blood pressure, heart disease, stroke, and chronic diseases.

"The important point is that noise is not just annoying," said Dr. Thomas Munzel, one of the researchers from the Johannes Gutenberg University, Germany. "One can close his eyes but not his ears. Our body will always react with a stress reaction."

This also explains why psychosocial well-being can be disrupted, especially in children. Constantly being exposed to loud and sudden sounds can result in annoyance, rage, anxiety, isolation, and more. They are also among the common triggers for people diagnosed with post-traumatic stress disorder.

Recently, WHO released environmental noise guidelines targeting the European region. The agency estimated around 40 percent of European Union residents were exposed to excess traffic noise levels, exceeding 55 decibels.

"These guidelines are evidence-based and health-based," said Stephen Stansfeld, a professor of psychiatry at the Queen Mary University of London who chaired the group that created the new guidelines.

While previous WHO guidelines have examined noise pollution, the new report has made a change by including the impact of leisure noise. More research may be needed as there is no universally accepted method of assessing the risk of hearing loss due to environmental noise exposure.

Apart from covering the aforementioned health risks, they also recommend that leisure noise levels should avoid exceeding an average of 70 decibels over 24 hours each year.

"This is equivalent to listening to a television at normal volume all day and all night throughout the year, not saying that you are going to do that, but your exposure to noise should average out at this level," Stansfeld explained.